Fluorinated compounds have a high potential in numerous fields of application. However, the use of many compounds is limited because of their method of preparation, which is sometimes expensive and/or difficult to implement.
For example, polyunsaturated perfluorinated compounds such as hexafluorobutadiene are used in the etching of electronic compounds. It is prepared by various processes involving C2 coupling reactions and fluorination with fluorine F2.
Another synthetic route consists in employing reactions for the fluorination of hexachlorobutadiene in the liquid phase. However, these reactions do not make possible the complete fluorination of hexachlorobutadiene to form hexafluorobutadiene. The fluorination of hexachlorobutadiene in the presence of potassium fluoride in order to form a mixture of 2,2-dichloroperfluoropropane and 2-chloro-2-hydroperfluoropropane is known in particular from U.S. Pat. No. 3,287,425.
The fluorination of perchlorohexatriene has also been demonstrated in the presence of SbF5 at a temperature of 150° C. to 300° C. (U.S. Pat. No. 2,431,969). The final product comprises 12% of chlorine, which implies a solely partial fluorination of the perchlorohexatriene.
There thus still exists a need to make possible the preparation of fluorinated polyene compounds by selective and affordable reactions.